'Nominal" means related to or functioning as a noun. "A nominal clause is a group of words, with a conjugated verb in it, that acts as a noun" (http://www.grammar.com/nominal-clause/). Then there's nominalization, "the use of a word which is not a noun (e.g. a verb, an adjective or an adverb) as a noun, or as the head of a noun phrase, with or without morphological transformation. The term can also refer specifically to the process of producing a noun from another part of speech via the addition of derivational affixes (e.g., legalize versus legalization)". (https://en.wikipedia.org/wiki/Nominalization) and http://www.grammar-quizzes.com/noun-forms.html For Hindi, you might find this article about nominal suffixes useful: http://blogs.transparent.com/hindi/nominal-suffix-in-hindi/

As per my understanding Nominal is normally use to represent a thought despite what the fact is.